I have a crf250x moto that I am in the process putting a new top end on.
I put a 250r head, a hot cam and weisco piston in. Everything else is stock.
I have everything installed to make the motor run and it does run and start just fine.
Started it for the first time and there is an abnormal noise in the motor.
Turned it off and removed and reinstalled the kick starter and that helped with some of the abnormality noise but something else still doesn't sound right.
Im not certain what to look for next.

I have shimmed the valves prior to starting can turn the motor over by hand using allen head with no abnormal noise that I can tell.

The motor has ran for maybe 30 seconds. How long does the motor take to prime the oil to the head?

1) Did you take off the side cover and remove the kickstarter mechanism? They can be a pain to get back in properly.I oringally had it in wrong. I took it out and put it back in. Some of the original bad noise is now gone. There are alignment marks on the kick starter that I didnt know of at the time.

2) Can/could you tell where the noise was coming from?Not really I think its maybe in the head/cam chain but havent let it run long enough in fear of damaging something.

3) Are you sure the cam chain tensioner is installed correctly (tension pulled OUT before installation)?Not certain about this one. What do you mean about tension pulled out? I installed the ACT with the pressure retracted, screwed it in and then let the tension out onto the cam chain. Ill go re-read the fsm.

4) All bolts were torqued properly (with a torque wrench).All bolts other than the case bolts have been torqued.

Does the kick starter engage in the same spot it did before and spring back to the same spot? I've put them in wrong and they make a nutty sound.

By the way, the pressure builds pretty quickly, but when I go in to the head/valves I always dump a little oil around cam just to make sure there is enough there on startup.

The first time I put it in the kick starter would move forward. The second time I put it back together it seems to stay in place.

I am going over everything in my head. I remember when I was test cycling the motor after putting all the working parts together to make sure nothing binded, that the compression cam was making noise.
I was thinking about it in the shower and haven't looked under the valve cover but I think this is the next place im going to look. The manual doesn't say much about it.

On the positive note, the motor starts super nice and with out hesitation unlike before. :-)

Another thing you may want to check is whether the cam bearings are seated properly. When I was assembling the top end on my 250x the grooves in the cam bearings did not want to seat in those races by themselves.

Thanks for the suggestion. I know full well of what you talk about. I had to take them out several times getting the shims with in correct number. I will look at that later today just in case I messed up. Pretty certain that the caps were sitting flush with the head part.

The noise increase's with speed.
So.. I took the valve cover off, poked and prodded. The valves are in tolerance all the way around. I cycled the motor through the strokes via the timing mark access, and didnt get the loud clank but a small one. It was caused by the compression cam. I took this out completely to eliminate probable causes.

I hooked the battery up and cycled the engine through use of starter motor. No loud or small clank.
I put an oil collector up to keep oil from everywhere and put the spark plug in and started it. I get loud clank. The noise seems to happen with a bit more rpm than turning by hand or electric starter.
If i was a guessing person I would now say it has something to do with the exhaust lobe/rocker arm.

Im too the point of completely disassembling the top end and starting again.

Here is a a hard description of the cycling of the cam. From 7-5:30 the cam moves smooth. Even with contact to the exhaust lobes its smooth. From the moment there is contact with the intake lifters there is 2 small pressure restrictions and then its smooth. Does this sound normal, about the pressure points on the cam lifters?

Thanks for the help guys and sorry for plugging up the BS thread with my tech questions.